PROJECT SUMMARY/ABSTRACT Dialysis-requiring acute kidney injury (AKI-D) is one of the most serious complications for hospitalized patients, with a rising incidence reported across several populations, including nationally in the U.S. While many published studies on acute kidney injury (AKI) and AKI-D have focused on identification of inpatient risk factors and characterization of clinical outcomes during the index hospitalization (i.e. inpatient death), less is known about the antecedent risk factors and long-term outcomes following hospital survival, such long-term dialysis dependence or death on dialysis. Meanwhile, the epidemic of end-stage renal disease (ESRD) remains a major public health burden, with a still growing number of prevalent patients requiring chronic renal replacement therapy (RRT) in the U.S., and high mortality rates especially early on after chronic dialysis initiation. The direct transition from having survived in-hospital AKI-D to dialysis-dependent ESRD is a known but not very well characterized problem, and may represent a particularly vulnerable group of individuals for poor outcomes. Dr. Raymond Hsu is an Assistant Professor of medicine (nephrology) at University of California, San Francisco, and has a growing expertise in AKI epidemiology and post-AKI clinical outcomes. The proposed study will to build on his prior work and to leverage comprehensive electronic healthcare data from the U.S. Veterans Health Administration (VA)?the largest integrated health system in the U.S.?in order to better define the contribution of AKI-D in incident, dialysis-depedent ESRD and subsequent clinical outcomes like death and renal recovery (from dialysis dependence). The proposal will also shed light on potential and novel predictors of those outcome, such as acute heart failure episodes and baseline (pre-AKI) proteinuria. The project?s aims are: Aim 1: To determine the association between antecedent AKI-D and subsequent all-cause mortality after incident ESRD, and to explore the role of preceding acute heart failure events Aim 2: To determine the association between baseline proteinuria level and chances of recovery from AKI-D (defined as recovery from dialysis dependence).